The approaches described in this section could be pursued, but are not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Enterprise application software has traditionally been delivered using three-tiered architecture, with a user interface tier, a server or business logic tier, and a database tier. These applications are typically deployed locally by a customer within their own data center, on their own hardware, and with their own support staff. Each application operates within its own “silo” of hardware, software, and support that does not leverage any of the resources that all such enterprise applications share. The initial cost to deploy an enterprise application with this architecture is substantial, in both dollars and time, and this initial cost has always been an obstacle to the sale of enterprise software to the small and medium business (SMB) market.
A two-tiered application architecture that relies upon a web browser-based client tier and a remotely deployed internet-accessible server tier to provide functionality that was previously delivered via a locally deployed three-tiered application is commonly referred to as software-as-a-service (SaaS) or Cloud Computing. A SaaS approach is intended to leverage the shared functions of computing applications, together with shared hardware, data, and support capacities, in order to provide a user experience with improved scalability, extensibility, maintainability, and with significantly reduced up-front costs. The term software-as-a-service (SaaS) is used as a blanket term for a set of features that uses a two-tiered network-accessible hosted service architecture.
The phrase “cloud computing” refers to an architectural paradigm in which computation is moved from local servers to a remote service that provides computation as a commodity or utility. A “cloud” is typically a large collection of shared commodity computation resources that can be interchangeably provisioned for client computation requests. Cloud computing is frequently used in SaaS application architectures and may be viewed as an implementation choice for application deployment that leverages shared resources and improved cost structure of the cloud. A cloud computing approach may be used to implement a variety of computational paradigms, such as virtual machines, jobs, remote procedure calls, traditional servers, etc.